Adding Equipment To The Outside Of Your Vehicle; Fuel; Gasoline Octane; Gasoline Specifications - Chevrolet 2008 Tahoe Owner's Manual

Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This can cause wind noise
and can affect fuel economy and windshield washer
performance. Check with your dealer/retailer before

adding equipment to the outside of your vehicle.

Fuel

Use of the recommended fuel is an important part of
the proper maintenance of your vehicle. To help
keep the engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies your
vehicle's engine. The VIN is at the top left of the
instrument panel. See Vehicle Identification Number
(VIN) on page 5-115.
If your vehicle has the 5.3L V8 engine (VIN Code 0) or
the 5.3L V8 engine (VIN Code 3), you can use either
regular unleaded gasoline or ethanol fuel containing up
to 85% ethanol (E85); also see Fuel E85 (85% Ethanol)
on page 5-7. In all other engines, use only regular
unleaded gasoline.

Gasoline Octane

Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you might notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. If you are using gasoline rated at
87 octane or higher and you hear heavy knocking, the
engine needs service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or
CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines
containing MMT. See Additives on page 5-6 for
additional information.
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